Lubricant-indicator for engine-crank cases.



G. D. BUCK LUBRICANT INDICATOR FOR ENGINE CRANK GASES.

APPLICATION TILED 001'. as, 1912.

1,068,626. Patented July 29, 1913.

Abbast, mvanbw'.

660. D um GEORGE I), BUCK, OF ST. LOUIS, MISSOURI.

imICANT-INIJICATOR FOR ENGINE-CRANK CASES.

Specification of Letters Patent.

Patented July 29, .1913.

1111681301 filed October 28, 1912. Serial No. 728,151.

My invention relates to an indicator for showing the depth of oil in thecr-ank case of the engine used in a motorcycle or automobile, the object being to produce an extremely simple, inexpensive and efficient indicator structure which may be readily appliedd to the crank case with which it is to be use Figure I is a side elevation of the lower portion of an engine crank case equipped with my lubricant indicator. Fig. II is a vertical section taken approximately through the center of the indicator.

In the accompanying drawings :A designates an engine crank case, one of the side walls of which is provided with two perforations 1, located in different horizontal planes, the lower perforation serving as a port for admitting oil from the crank case to the well of the indicator, and the upper perforation serving as a vent from said well to the interior of the crank case. The indicator comprises a member provided with a sight opening, said member being preferably a ring 2 arranged around the perforations 1 and secured to the crank case by screws 3. A glass plate 4 closing the sight opening in the ring 2 is arranged within said ring a and located between packing gaskets 5 and 6.

7 designates an externally screw threaded ring fittedto internal screw threads in the outer ring 2, and bearing against the gasket 6. The threaded ring 7 is preferably provided with notches 8 for the reception of a;

suitable tool by which it may be adjusted to compress the gaskets 5 and 6, thereby producing a tight joint bet-ween the gasket 5 and the -wall of the crank case around the perforations 1, and at the same time firmly the adjacent wall of the crank case A. It will be noted that the background of the sight opening is a portion of the crank case which may be cleaned from time to time upon the removal of the threaded ring 7 and glass plate 4.

The most salient feature of my present impnovement resides in an indicator of the kind described having as essential elements thereof a crank case part in which there are perforations at different elevations, or in different horizontal planes, a transparent plate separated from such perforated part, and a well in which the transparent plate is included into which lubricant may enter the well by passing through a lower perforation in the perforated part, an upper perforation in such part furnishing an air vent between the well and the interior of the crank case. The advantage of this construction lies in the fact that it provides separation of the well from the interior of the crank case in a manner which permits of the lubricant entering readily into the well of the indicator to a level corresponding to the level of the lubricant in the crank case when the engine mechanism in the crank case is at rest, and with-out opportunity for the lubricant in the crank case being splashed against the transparent plate of the indicator when the engine mechanism is in operation. In this connection, it should be explained that when the engine mechanism is placed in operation, the lubricant is drawn by suction from the indicatpr through the lower inlet perforation 1 in the crank case wall, and there is absence of lubricant in the indicator well throughout the period of operation of the engine. "When the operation of the engine'is discontinued, the lubricant passes through the lower and inlet perforation 1 into the well of the indicator until it reaches a level therein corresponding to the level of the lubricant in the crank case; and as this occurs, the air in the indicator well is vented through the upper perforation 1 into the crank case, instead of remaining in the Well to act as an air cushion that would prevent free entrance of the lubricant into the indicator well.

I claim 1. The combination with an engine crank case having a wall provided with perforations in different horizontal planes, of a sight member carried by said wall extending around said perforations, the said member a transparent plate having a sight opening,

' means for sepaclosing said openmg, and

rating said transparent plate from saidcrank case wall to produce a well in communication with the interior of said crank case through said perforations.

2. The combination with an engine crank case having a wall provided with perforations in different horizontal planes, of a well forming member jutting outwardly from saidcrank case wall and encircling said perforations, and a transparent plate in said well forming member spaced away from said crank case wall.

3. The combination with an engine crank case havin a wall provided with perforations in di erent horizontal planes, of an internally threaded rin secured to said wall and arranged around said rforations, a transparent plate within sai ring, a gasket separating said transparent plate from said perforated crank case wall to produce a well communicating with the interior of said crank case, and an externally threaded ring screwed into said internally threaded ring to firmly hold said transparent plate agamst said gasket.

4. A lubricant indicator for van engine crank casecomprising a crank case part having perforations in different horizontal planes, a well member surrounding said perforations and extending laterally from the part provided with the perforations, and a transparent closure for said well member opposite and spaced from said perforated part.

GEO. D. BUCK. In the presence of-- A. J. MCCAULEY, E. B. LINN. 

